Retractable cover with biasing mechanism for covering structures

ABSTRACT

A retractable cover which includes a flexible material portion having at least one biasing mechanism. The biasing mechanism is a spring with either constant or varied force that allows the flexible material to be rolled up. The retractable cover is particularly applicable to tents or temporary structures, but could also be applied to window covers, awnings, truck sidings boat canopies or the like. The biasing mechanism may be placed in a sheath which includes a zipper or the like, so that the biasing mechanism can be easily replaced or added to. Additionally, zippers can be positioned at the sides of the retractable cover to allow the securing of the cover at any height.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a retractable cover with biasing mechanism forcovering structures.

In particular, it relates to a retractable cover that includes aflexible material portion and at least one biasing means enabling thecover to automatically retract from an extended state and thus allowsthe flexible material to be rolled up. The retractable cover isparticularly applicable to tents or temporary structures, but could alsobe applied to window covers, awnings, truck sidings, trailer covers,boat canopies, or the like. However, the present invention may also haveother applications outside this field.

2. Description of the Related Art

The general method of covering an opening, enclosure or outdoor area isgenerally by a window, door, or a covering of some description.

The term “door” or “window” usually refers to a solid structure in ahouse or the like which can be transparent, translucent or opaque. Inthe case of a more temporary or flexible structure with an entranceopening, the need for a flexible cover that does the same job as a dooror window becomes necessary.

A cover can be something used to protect an underlying surface, enclosean opening, or provide a shield, a wall, or a limitation.

In the example of a tent, a cover can include the “roll down” orzipper-type of cover that is positioned over a window or door to blockout the elements, keep out insects, block light, or provide privacy.

In the example of a transport truck or the like, a cover can be the sideflap on the trailer that covers stored goods for transport. For atrailer or utility truck deck, the cover can be a typical trailer coveror truck deck cover that covers articles in the trailer or truck deck.

In the example of a caravan, stall or shop, a cover can be the temporaryroof that provides shelter from the sun or the elements to protect theunderlying items.

In the example of a boat, a cover can be an awning or temporary roofthat also provides shelter from the sun or the elements to protect theunderlying persons or items.

In many situations where there are varyingly sized receptacles,containers and the like that require a temporary or permanent covermeans, the cover can provide the ability to close off the receptacle orcontainer from access, from the weather elements, and so forth.

In all cases where a cover is required, the means of storing the coverwhen not in use, the application of that cover when required, and theprocess of manipulating the same cover for either or both use andstorage, can be both tedious and time consuming.

When a person is camping in a tent or residing in a caravan awning,securing or storing the window or door covers is a tedious process. Inpoor weather situations, the time taken to put a cover in place can leadto the person getting cold or wet.

In a freight-trucking situation, folding back a cover to expose goodsfor transfer can take time and restrict access to goods while unloading.Any time saved while undertaking a job allows the user to be moreeconomical and provides the possibility of fitting more activities intoa day, providing potential for higher earnings.

In the case of a stall, caravan or shop, the ease of application andremoval of a cover allows attendants more time on other jobs, increasingefficiency.

Current inventions address the problems of storage of the covers bymeans of enclosures, or the like. They also address the problem of quickextension and retraction of covers, but in all cases the proceduresrequire either complex mechanisms, or a series of support systems. Noneof the current inventions provide for a quickly retracting cover that issimple, compact, and in the case of a tent or awning, can beincorporated into the design of the tent or awning without substantiallylimiting the packing size.

A built-in awning for a recreational vehicle is described in WO93/09005. A longitudinal reel is included within a recess in a side wallof the recreational vehicle. The reel is adapted to carry a length ofawning material, and there are provided means for rotating the reel inorder to wrap and unwrap the awning material on/from the reel. To rotatethe reel the rotating means are manually operated, or effected by theoperation of an electric motor means.

Another version of a retractable cover is described in U.S. Pat. No.6,053,556 which relates to a retractable cover for truck beds. The covercomprises a rectangular shaped flexible web having a front end fixed tothe shell of a spring powered roller. The roller is fixed by brackets toeither side of the truck bed. A pull strap allows retraction andextension of the cover by an operator from the back of the truck.

United Kingdom Patent Application Number 217,375A also describes asimilar motor vehicle and trailer protection which comprises at leastone flexible sheet material, provided in rolled form and stored in aholder. Before the flexible cover is unrolled from the holder, theholder is secured to the vehicle or trailer via brackets whichco-operate with and/or are secured in place by the closed boot lid, aclosed rear window of a hatchback car, or a car bumper. The holder, inthe form of an elongate box or cylinder, includes a longitudinal slotthrough which the cover is fed. A spring-loaded roller is included inthe holder, to which one end of the flexible cover is attached. Thecover includes stops at its opposite end to prevent the cover beingfully retracted into the holder by the operation of the spring-loadedroller when tension of the extended cover is released and the cover isto be retracted. The roller is spring-loaded so as to always urge thecover to be rolled up on the roller.

All of the above systems rely on the use of a roller around which theunwrapped material cover is rolled. After use, the roller may be rotatedby spring mechanisms, electric motor means, or manual rotation systemsto roll the cover up. Such systems may be bulky, include a number ofparts which may become damaged, or worn and require replacement, and donot allow for different extensions of one elongate side edge of thematerial compared to the other such that the cover may lie partiallyunwound in a substantially diagonal arrangement across the opening orstructure, to enable the opening or structure to be only partiallycovered, if required. Further, for some of these systems, the holder isa cumbersome object which is required to be fitted to the structure,requires storage when not in use and is not compact. Further, the damageto the helical spring or winding mechanisms, or weakening thereof, mayresult in no, or imperfect, retraction of the cover into the holder.

A different means of effecting a flexible retractable door is describedin U.S. Pat. No. 5,332,021. This invention uses sheet polyester film,for example, composed of commercially available “MYLAR”, which has apermanent memory, is set to roll up on itself, or otherwise to retractautomatically into a coil. The memory of the material minimizes the needto include separate winding apparatus. The material is not substantiallyflexible as may be canvas, thinner plastics materials, rubber and soforth. It is the rigidity of the material that permits it to retain itscoil memory and allows the door to operate as it is described in thepatent.

Such material however would not be suitable as covers for tent doorwaysor windows, or for vehicle trailers, or as awnings where there is a needfor greater flexibility of material, a need to roll up the covers to besubstantially compact, and so forth. Further, the potential coilingtension of the polyester sheet as a whole may limit the use of thismaterial in situations where it would be useful to extend only oneelongate side edge of the material in a manner which creates asubstantially diagonal arrangement across the opening or structure, toenable the opening or structure to be only partially covered, ifrequired, such as is often the case for a tent doorway, tent windowcovers, or the sides of awnings. Further, in its various applications,it includes a means to contain or retain the coiled material.

Therefore, these above mentioned examples and other available devices donot address the problems which the present invention seeks to address.

While the present invention has a number of potentially realizableapplications, it is in relation to problems associated with suchexisting systems that the present invention was developed. Morespecifically, it was with the problems associated with the lack of areadily available alternative system for achieving a cover capable ofbeing quickly extended or retracted without the need for cumbersomesystems such as rollers, or holders; therefore, a cover which may bemade of a range of flexible materials as applied to tents, awnings, boatcovers, trailer or truck deck covers, and so forth.

In addition, having a simple system capable of being easily installedwould benefit those with pre-existing covers on their tents, or withawnings or covers used for recreational vehicles, trailer or trucks, orshop frontages. It would further benefit those wishing to install such asystem as part of a new design.

It would be useful therefore to have a system that:

-   -   could have the benefits of being fitted to existing material        covers as required; yet    -   could be accommodated into new covers; and    -   could be permanently or temporarily installed; and    -   could be less bulky than previous systems; and    -   could enable the cover to be partially or fully extended, even        to create a diagonal opening; and yet    -   could be used with covers of various shapes, sizes and weights;        and    -   did not require complex mechanisms, or means that included        multiple parts, to wrap up or unwrap the cover.

It would therefore be advantageous to have an invention that offered atleast some if not all of the advantages of the above proposedretractable cover.

BRIEF SUMMARY OF THE INVENTION

It is therefore an object of the present invention to consider the aboveproblems and provide at least one solution which addresses a pluralityof these problems.

It is also an object of the present invention to provide a system whichallows for a substantially trouble free installation.

Ideally the system is suitable for use, or is suitable to being adaptedfor use, in situations where existing or new covers are used or are tobe used, as well as providing a range of other possible locations foruse not previously considered to be practical.

It is also a further object of the present invention to provide aretractable cover that can be operated by a single operator in a varietyof applications.

Finally, it is an object of the present invention to at least providethe public with a useful choice or alternative system.

All references, including any patents or patent applications cited inthis specification, are hereby incorporated by reference only. Thisreference does not constitute an admission that any of these documentsform part of the common general knowledge in the art, in New Zealand orin any other country. The discussion of the references states what theirauthors assert, and the applicant reserves the right to challenge theaccuracy and relevance of the cited documents.

It is acknowledged that the term “comprise” may, under varyingjurisdictions, be attributed with either an exclusive meaning or aninclusive meaning. For the purpose of this specification, and unlessotherwise noted, the term “comprise” shall have an inclusive meaning;that is, that it will be taken to mean an inclusion of not only thelisted components it directly references, but also other non-specifiedcomponents or elements. This rationale will also be used when the term“comprised” or “comprising” is used in relation to one or more steps ina method or process.

Further aspects and advantages of the present invention will becomeapparent from the ensuing description which is given by way of exampleonly. It should be appreciated that variations to the describedembodiments are possible and would fall within the scope of the presentinvention.

According to one aspect of the present invention, there is provided aretractable cover which includes a flexible material portioncharacterized in that the flexible material includes at least onebiasing means.

The biasing means is further characterized in that it isself-retracting. Accordingly, the biasing means itself has a permanent,or substantially permanent, coil memory to enable it to roll up onitself when released from an extended orientation.

The biasing means effects retraction of the flexible material portionfrom an extended orientation to a retracted, rolled orientation. Thelocation of the biasing means on, or in relation to the extendablelength of, the flexible material portion is determined by the preferreddirection of retraction of the flexible material portion.

In prior art systems previously described, the biasing means is attachedat least in part to a roller, often located within a holder and not tothe substantially extended length of the flexible material itself. Thuswhen the covers of such prior art systems are retracted the cover isfully wrapped on the roll. In such systems as that described in U.S.Pat. No. 6,053,556 and United Kingdom Patent Application Number217,375A, and also in U.S. Pat. No. 5,332,021, the biasing meansincludes a helical spring connected at one end to a roll. The spring inthe roll provides the retracting force when the cover is extended. WO93/09005 describes a motor operated, or a manually operated, rewindingoption.

The system as described in U.S. Pat. No. 5,332,021 relies on the coiledmemory of the material from which the actual cover itself is made.

By comparison, in the present invention, it is the biasing means thatextends along all or a substantial portion of the extended length of theflexible material that provides the retracting force when the flexiblematerial is extended. This provides some advantages over the prior artin that a separate roller is not required; the biasing means may be usedto provide the desired retraction of all or even only a portion of theflexible material; and cumbersome additional features such as storageboxes, holders, or containers are not required to house the spring androller mechanism, or the self-coiling substantially rigid cover materialwhen coiled. Rather, one end of a range of flexible materials, with thebiasing means in place, may be directly attached to a portion of thestructure substantially in the vicinity of the area or the structurerequired to be covered. The cover with included biasing means is notbulky. The means of attachment of the cover including the biasing meansmay be a permanent or temporary arrangement. The inclusion of thebiasing means with the actual flexible material may also be permanent ortemporary.

With existing covers on boats, tents, houses and buildings, the existingsystems typically offer simply an up or down option. There is typicallyprovided no maintainable mid-way or angled position for the flap orcover. The height of the cover is unable to be controlled means that theuser is therefore unable to control the light, air, or weather fromentering, for example, a doorway or window of a tent. It is alsogenerally a tedious affair having to roll up covers of boats, tents,trucks, and awnings. Further, rolling by hand is perhaps the single mostfactor that destroys the quality of clear covers through scratching,cracking, marking and fingerprints, and so forth.

The term “biasing means” in accordance with the present invention shouldbe understood to include a means that causes the flexible material tomove from an extended state to a compact or retracted position. This,for example, could include a strip which is under toroidal tension whenin an extended state, e.g., elastic rubber or a tensioned metal stripsuch as a spring or a constant force spring. However, these are listedby way of example only and should not be seen to be limiting in any way.

In some embodiments, the biasing means is a constant force spring.

In preferred embodiments, the spring is a varied force spring, sodesigned that when in an extended state, the spring will begin toretract with a lesser degree of force compared to when it is in apartially retracted state. As the spring retracts further, it will do sowith greater force. This is an advantage when affixed to a flexiblematerial, as the weight of material to be moved into a compact orretracted state, when in a fully extended state, is less than when thespring is partially retracted. When partially retracted, there is agreater weight of material to retract, so the increased strength of thespring allows the retraction to continue unaided and substantiallyunimpeded.

Varied force springs can include commercially available “ELGILOY”-basedsprings and commercially available “INCONEL”-based springs.“INCONEL”-based springs are high performance nickel alloy based springsthat are corrosion resistant. “ELGILOY”-based springs arecobalt/chromium/nickel rich alloy springs with excellent fatigue life,with corrosion resistance in numerous environments, and arenon-magnetic.

This biasing means allows the cover that it is incorporated into toautomatically retract on release of the cover from its extended state.

The term “flexible material” in accordance with the present inventionincludes materials such as fabric, canvas, plastic, mesh, nylon, rubberor any material that is substantially flexible and may be used with thepresent invention.

The flexible material portion is characterized by the location of thebiasing means on, or in relation to at least a substantial portion of,the overall extendable length of the flexible material portion. Further,this arrangement of the biasing means, relative to the actual flexiblematerial itself, lends an added feature to the present invention in thatthe flexible material may take other than a rectangular shape. Forexample, the retractable cover may be circular, triangular, and soforth. The shape need not be impeded by the dimensions or requirementsof a spring loaded roller, or of a holder for containing the retractedcover. The ability to select a preferred flexible material from a rangeof suitable options, from canvas, to webbing, to rubber, to plasticmaterial sheeting, of various thickness, and so forth enables thepresent invention to provide a degree of choice that may be morerestrictive in previous systems.

The use of such biasing means in association with a range of flexiblematerials as assembled in accordance with the present invention asherein described, or as may be adapted to include, provides an improvedalternative for the existing cover systems as discussed in examplesdescribed herein. Covers of different materials and weights may beaccommodated by determination of the required coil spring energycharacteristics of the biasing means.

Further, the present invention allows for retraction of one side lengthof the cover, but not the other, to create a partial opening as may berequired in particular circumstances, such as entry and exit to a tent,partial closure of a window opening, access to only a portion of atrailer of truck deck, and so forth. Prior art systems referred to donot provide for such flexibility of operation.

In preferred embodiments, the retractable cover is used to coversurfaces. The surface could include an opening, area, or enclosure, aspart of a structure. For example, as already referenced, the structurewith which the retractable cover may be used may include tents as acover for windows and doors, awnings for attachment to tents,recreational vehicles, or buildings, covers for trailers or truck decks,the flexible side walls of larger transport trucks and the like.However, these are listed by way of example only and should not be seento limit the scope of this invention in any way.

The term “opening” in accordance with the present invention should beunderstood to include a door, a window, or a cat flap or the like, butthese are also listed by way of example only and should not be seen tobe limiting in any way.

The term “area” in accordance with the present invention should beunderstood to include a surface such as a wall, floor or the like, wherea picture, drawing or feature is to be covered; however, these are alsolisted by way of example only and should not be seen to be limiting inany way.

The term “enclosure” in accordance with the present invention should beunderstood to include a tent, caravan awning, house, caravan, trucktrailer, stall, shop, fireplace, box or container; however, these arelisted by way of example only and should not be seen to be limiting inany way.

According to another aspect of the present invention, there is provideda method of inclusion of a biasing means, as described above, with anexisting cover for covering a structure characterized by the step ofincorporating at least one biasing means to an existing cover.

This has the advantage of allowing an existing covering for a structureto be made into a retractable form by the addition of biasing means. Thebiasing means could be attached by a bonding glue or be sewn in, orencased in a full or partial sheath that could either then be sewn ontothe cover, or be incorporated into the design of the cover initially byfolding the cover to form a sheath and sewing down each side of it tosecure it in place. Alternatively, the biasing means may be held inplace by the inclusion on the cover of multiple tabs, loops or similarretaining means. The biasing means is then included on the cover bythreading it under the tabs, through the loops and so forth.

In some embodiments, where whole and/or partial sheath housings areincluded, the biasing means could include a zipper, a hook-and-pilesystem, buttoned or press stud arrangements, or similar, running thelength of the sheath portion so that the biasing means could beinstalled, checked, replaced, or maintained, or to increase the numberof biasing means over and above that number originally used in order toincrease the overall strength of the bias, or to reinforce the biasingmeans, if for example, the choice of application of the cover hadchanged and a stronger biasing means was required.

It should be appreciated that the term “sheath” in accordance with thepresent invention should be understood to mean a cover, fitted ortemporary, that encases a whole or part of the biasing means. The sheathcould be made of fabric, plastic, rubber, or the like. However, thesheath may be made of any suitable material and these are listed by wayof example only and should not be seen to be limiting.

For example, the sheath may cover the entire length of the biasingmeans. Alternatively, the sheath may be included at each distal end ofthe biasing means. The sheath may operate to provide protection of thebiasing means from corrosion or the like, or to enable the biasing meansto be affixed to an existing or new structure, or where the edges of thebiasing means may be sharp or have the tension to rip through a flexiblecover, the sheath may be end portions on the biasing means to protectthe user and/or the flexible material. The end sheaths, partial sheathsand full sheaths may be used in any combination with each other, orsingularly.

According to another aspect of the present invention there is providedsecuring means for securing a retractable cover as described above to anexisting structure.

According to another aspect of the present invention there is provided aretractable cover including securing means, characterized in that thesecuring means is adapted to attach the retractable cover to astructure.

The term “securing device” in accordance with the present inventionshould be understood to include a means that allows the retractablecover to be attached, in its entirety to an existing structure. Thismeans could include a hook-and-pile fastener, also known as ahook-and-loop fastener, such as commercially available “VELCRO”;buttons; domes; or metal clips. These options are, however, listed byway of example only and should not be seen to be limiting in any way.

The general operation of the retractable cover will depend on thestructure with which it is used. For example, a cover for a window, orenclosure, may preferably be extended and retracted vertically, in anup-down direction; a cover for a door or similar opening may be extendedand retracted laterally/sidewise, in a left to right direction; anawning or cafe outdoor seating cover may be extended and retractedhorizontally, or at any appropriate angle.

This embodiment has the advantage of providing a quickly retractingcover that is simple, compact, and in the case of a tent or awning, canbe incorporated into the design of the tent or awning without limitingthe packing size in any substantial way.

A number of biasing means can be incorporated into a cover of, forexample, a tent window or door, allowing, on release of any securingdevice, the cover to retract to the top of the window or door, where itcan be secured by a hook-and-pile fastener such as commerciallyavailable “VELCRO” or the like. This means that for a small cover only asingle biasing means might be required, but on a larger door or windowcover, a number of biasing means could be incorporated to ensure thereis enough strength to cause the cover to retract when the cover isrequired to be opened or lifted.

As previously mentioned, it should also be appreciated that severalbiasing means may be incorporated into a single sheath or the like, toincrease the strength of the retracting means, or to reinforce the firstspring if the application of the cover has changed or the strength ofthe spring has decreased over time.

Given the natural orientation of the biasing means dictates a preferencefor the cover to urge towards a retracted state, it is necessary in use,when the cover is extended, for there to be included affixing means toensure the cover is retained in the extended state for a preferredperiod of time. Affixing means to maintain the cover in an extendedorientation may include any or a combination of a hook-and-pile fastenersystem such as commercially available “VELCRO”, buttons, material ties,clips, magnets, zippers, or hooks, but these are examples only andshould not be seen as being limiting in any way.

The affixing means may be located around the structure in locationscomplementary to and substantially along the whole or part of thestructure equating to the length of the cover when extended.Alternatively, the affixing means may be located only at a position onthe structure equating to the fully extended position of the cover. Thenumber, type and positioning of the affixing means will tend to bedetermined by any one or a combination of the structure with which thecover is used, the pressures applied to the cover when extended, such asstrong winds, the length of the cover when fully extended, the strengthof the biasing means, the material from which the cover is made, and soforth.

Means for enabling a retracted cover to be pulled to an extended statemay include a string tied to the ends of the cover, or elastic cords,loops or other means that may be gripped and pulled. Again, the examplesprovided herein are by way of example only and should not be seen asbeing limiting in any way. Any suitable means may be available in theprior art, or may be adapted for use with the present invention.

In a preferred embodiment the retractable cover could be applied to atent window, whereby the cover is affixed to the tent by means ofzippers down each side of the cover. Upon retraction of the zippers to ahalf way position, the cover would retract to that position also,allowing for the window to only be half covered, or at any positionwhere the zippers, singularly or together, would be retracted to. Thishas the advantage of allowing in a limited amount of light or air forcirculation, adjustable to personal preferences.

In another preferred embodiment, the retractable cover attached to atent window would be accessible from the inside, if the mesh coveringthe window were attached by a zipper. The mesh zipper could be undoneand the window cover accessed and adjusted, then the mesh zipper is doneup again. This has the advantage of allowing the window cover to beadjusted without having to step outside.

Use of the retractable cover in the trucking industry allows for quickretraction of covers, speeding access to goods and ensuring the cover iskept out of the way of loading and unloading. Use of the same cover inoutside cafes and stalls and the like to create shelter against theelements allows for quick packing up of a site at closing, and easystorage of the covers when not in use. The ability to attach the samecover to a cafe or stall by a detachable means such as a hook-and-pilefastener also has the advantage of allowing the covers to be broughtinside overnight and therefore protected from the elements, theft orvandalism.

It should be appreciated that the present invention lends itself to morethan one application. Hence, the invention may be adapted for use in anylocation, with a range of building structural features, having a rangeof dimensions, and/or for use with vehicles and recreational structures,be variable in terms of the strength of the biasing means and theflexible material used, and so forth. As can be appreciated variationsto and from the above described embodiments may be made withoutdeviating from the scope of the present invention.

It should further be appreciated a variety of different embodiments,uses, and applications of the present invention therefore exist, evenwithin the ambit of the above described security box system. Anembodiment of the present invention will now be given by way of exampleonly, to help better describe and define the present invention. However,describing the specified embodiment should not be seen as limiting thescope of this invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Further aspects of the present invention will become apparent from thefollowing description which is given by way of example only and withreference to the accompanying drawings in which:

FIG. 1 is a diagrammatic perspective representation of a retractablecover including biasing means and in a retracted state, in accordancewith one embodiment of the present invention;

FIG. 2 is a diagrammatic perspective representation of a retractablecover including biasing means and in an extended state, in accordancewith one embodiment of the present invention;

FIG. 3 a is a diagrammatic perspective representation of a tentincluding a retractable cover over a window opening including biasingmeans and in a retracted state, in accordance with one embodiment of thepresent invention; and

FIG. 3 b is a diagrammatic perspective representation of tent in whichthe retractable cover including biasing means enables the tent to bedisassembled in a compact state without the need to detach the covers,in accordance with one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the diagrams by way of example only, there is provideda retractable cover 1 with biasing means 5 for covering structures 3.

The cover 1 as illustrated in FIG. 1 is made from substantially flexiblematerials, such as fabric, canvas, plastic materials, rubber, and soforth. The cover 1 includes a top edge 1 a, a bottom edge 1 b, and twoside edges 1 c. The cover 1 is substantially rectangular in shape.However, the shape of the cover 1 is variable between embodiments and isdictated by the structure's size and shape with which the cover is used.

The cover 1 may be secured in relation to the structure, at any one ormore of the edges of the cover, depending on the function the cover isdesigned to fulfill. The structure it is covering, in the illustratedexample, is an opening 2, such as a window or doorway of a tent 3, forexample. The cover is therefore secured to the surround adjacent thestructure. In the illustrated examples, the cover is secured to the topperiphery 4, or top edge of the tent window opening 2 it is designed tocover.

In the illustrated embodiment, the cover 1 is secured in either apermanent or removable manner at its top edge 1 a. The actual type ofmeans 4 a of securing the cover 1 to the structure periphery 4 a are notillustrated per se, but are represented by simple diagrammatic referenceat 4 a. The securing means 4 a may include being sewn onto the peripheryof the structure, affixed by a hook system, by a hook-and-pile system,by a dome or buttoned system, or by screws, pins, adhesives, welding andso forth.

FIG. 1 illustrates an embodiment where the retractable cover 1 is in aretracted state. Retraction of the cover is effected by the inclusion ofbiasing means 5. In FIG. 1 a set of two biasing means 5 a and 5 b areincluded with the cover. The biasing means are located substantiallytowards both side edges 1 c of the cover and extend substantially thefull vertical length of the side edges. The strength of the biasingmeans and preferred coil memory of the biasing means is designed toeffect retraction of the cover from a tensioned extended state to acoiled retracted state, with little effort on the part of the user. Thisbiasing means 5 is selected to allow the cover 1 that it is incorporatedinto to automatically retract on release of the cover from its extendedstate.

In addition, the preferred biasing means comprises a varied forcespring, so designed that when in an extended state, the spring willbegin to retract with a lesser degree of force compared to when it is ina partially retracted state. Thus, as the spring retracts further, itwill do so with greater force. This is an advantage when affixed to aflexible material, as the weight of material to be moved into a compactor retracted state when in a fully extended state, is less than when thespring is partially retracted. When partially retracted, there is agreater weight of material to retract, so the increased strength of thespring allows the retraction to continue unaided and substantiallyunimpeded.

The biasing means 5 preferably are composed of stainless steel and mayin some instances be modified to suit corrosive environments.

For inclusion of the biasing means to existing structures, the biasingmeans 5 may be available in predetermined lengths, for example, threemeters for use on tents and boats. The biasing means are preferablysimple cut to length to suit the particular application using a pair ofscissors, or tin snips will suffice.

The biasing means may have a “force”, such as a spring constant orrestorative force, ranging from about 0.25 kg to at least about 50 kg,or equivalent force units such as Newtons. However, it may be preferableto err on the side of weaker rather than stronger and use the biasingmeans in the cover as an aid rather than a tool, since too strong abiasing means may stress the fabric and associated accessories. Whilstthe above “force” range is preferred for covers for the likes of tents,boats, awnings and truck side walls, other biasing means for variousother covers may have a “force” lesser than or greater than the abovespecified range. Accordingly, the range may vary depending on theflexible material used, the dimensions of the surface required to becovered, and so forth.

The biasing means may be plain, or encased in a sheath made from PVC, orother suitable materials, or with a thick durable glue lined sheath.

In FIG. 1 the biasing means are directly attached to the cover byrestraining means, such as a bonding adhesive, although welding may alsobe an option.

Affixing means 6, for affixing the cover into position when extended,are also shown. The affixing means may be a hook-and-pile fastenersystem such as commercially available “VELCRO”, buttons, material ties,clips, magnets, zippers, or hooks.

In the embodiment of FIG. 2, the cover 1 is in a fully extended state.The biasing means 5 in this embodiment are encased within a sheath 7either partially or completely. The sheath is arranged relative to theextendable length of the flexible portion and restrains the biasingmeans in a predetermined location on the flexible material portion. Thisfigure illustrates a range of possible sheaths. The sheath 7 on the lefthand side of the cover is designed to cover the entire biasing means 5.The sheath may be made from the flexible material and added to thecover, or be included in the cut of the flexible portion such that, whencompleted, the sheath is integrally formed as part of the cover design.The biasing means on the right hand side of the cover includes onlypartial sheaths 7 which may operate as end caps for the biasing means,or be loops, tabs or other spaced apart retaining means. Any option or acombination thereof may be used for the biasing means of variousembodiments. Only three options have been illustrated, but othervariations of sheath configuration are also possible.

Other means for restraining the biasing means in relation to theflexible material portion include a hook-and-pile system attached bothto the flexible material portion and to the biasing means in acomplementary manner and attachment apparatus, including screws, bayonetfittings, domes, buttons. However, as can be appreciated, there arenumerous equivalents available for use as restraining means, or that maybe adapted for use as restraining means.

Means for enabling a retracted cover to be pulled to an extended statemay include a string 8 tied to the end of the cover, or elastic cords,loops or other means that may be gripped and pulled.

With reference to FIG. 3 a there is illustrated one embodiment of use ofthe present invention. The tent 3 is illustrated with a retractablecover 1 positioned over an opening 2, being either a window or a door.As can be seen from the figure, it is possible to retract the coverpartially at 2 a to uncover only a portion of the surface of the window2, or release on one side of the cover to create a diagonal opening 2 bwith the door 2. This ability to partially retract the whole or part ofthe cover provides greater flexibility than offered by prior art systemsfor opening the cover to reveal the structure.

FIG. 3 b illustrates an envisaged advantage that may be gained not onlyby the convenience of the automatically retractable cover 1, but also bythe ability to disassemble and fold the tent 3 to a compact size 9without detaching the cover 1. The retraction mechanism does not providea substantial limitation to the compactable size of the tent 3.

The biasing means 5 by way of example only includes a spring, withparticular reference to a varied force spring, but this example shouldnot be seen to be limiting in any way.

Similarly, the direction of the retraction of the cover, as representedin FIG. 1 is by way of example only and should not be seen as limitingin any way.

Also the number and location of the biasing means on the flexiblematerial cover 1, the means of securing the cover adjacent the structureit is to cover, the means of affixing the cover in an extended state fora preferred duration of time, and the means of pulling the retractedcover to its extended state are also all represented by example only andshould not be seen to limit variations to the invention.

Accordingly, the present invention provides a retractable cover withbiasing means that provides:

-   -   a cover for surfaces;    -   a cover that may be both easily and quickly extended and        retracted by a single operator over varyingly sized structures;        and    -   a cover which is low in cost, simple to maintain, and easy to        install.

The cover provides for an easy, relatively inexpensive method forrolling up covers whether on a house, tent, boat, building, truckflexible side walls, trailers of utility truck decks, containers orreceptacles of varying sizes and shapes.

Again, it should also be understood that the term “comprise” where usedherein is not to be considered to be used in a limiting sense.Accordingly, “comprise” does not represent nor define an exclusive setof items, but includes the possibility of other components and itemsbeing added to the list.

This specification is also based on the understanding of the inventorregarding the prior art. The prior art description should not beregarded as being an authoritative disclosure of the true state of theprior art but rather as referring to considerations in and brought tothe mind and attention of the inventor when developing this invention.

Aspects of the present invention have been described by way of exampleonly and it should be appreciated that modifications, additions andvariations to and from the above described embodiments may be madewithout deviating from the scope of the present invention as defined inthe appended claims.

1. A retractable cover for covering structures, the cover comprising: aflexible material portion including thereon or adapted to include meansfor attachment of at least one biasing means along the extendable lengthof the flexible material portion, the at least one biasing meansproviding for retraction of the flexible portion from an extended stateto a rolled-up state.
 2. The retractable cover as claimed in claim 1wherein the biasing means is of a length relative to at least apredetermined extendable length of the flexible material portion.
 3. Theretractable cover as claimed in claim 2 wherein the biasing means is aspring.
 4. The retractable cover as claimed in claim 3 wherein thebiasing means is a constant force spring.
 5. The retractable cover asclaimed in claim 3 wherein the biasing means is a variable force spring.6. The retractable cover as claimed in claim 5 wherein, where thebiasing means is a variable force spring, the retraction force of thespring can be selected from a range of about 0.25 kg to about at least50 kg as determined by one or more of at least the weight of theflexible material portion, the dimensions of the flexible portion, andthe structure to be covered.
 7. The retractable cover as claimed inclaim 4 wherein the biasing means is restrained permanently to theflexible material portion via use of restraining means selected from thegroup consisting of: a) an adhesive; and b) welding means.
 8. Theretractable cover as claimed in claim 4 wherein the biasing means isprovided in a removable relation to the flexible cover via use ofrestraining means selected from the group consisting of: a) ahook-and-pile system attached both to the flexible material portion andto the biasing means in a complementary manner; b) a full sheath capableof enclosing a substantial portion of the biasing means; c) a partialsheath capable of providing retaining means to one or more designatedportions of the biasing means; and d) attachment apparatus, includingscrews, bayonet fittings, domes, and buttons.
 9. The retractable coveras claimed in claim 8 wherein the flexible material forms the sheath.10. The retractable cover as claimed in claim 9 wherein the sheath issewn on to the flexible material.
 11. The retractable cover as claimedin claim 9 wherein the sheath is configured to allow access to thebiasing means.
 12. The retractable cover as claimed in claim 11 whereinthe sheath includes a zipper.
 13. The retractable cover as claimed inclaim 12 wherein either or both the flexible material portion and thestructure includes means for securing the cover relative to thestructure with which the cover is used.
 14. The retractable cover asclaimed in claim 1 wherein the retractable cover includes at least oneaffixing means for removably restraining the cover in an extended formto cover a surface of the structure with which the cover is used. 15.The retractable cover as claimed in claim 14 wherein the affixing meansenables the cover to be restrained at any position along its extendablelength to effect a partially or completely rolled-up cover as required.16. The retractable cover as claimed in claim 15 wherein the affixingmeans is at least one zipper.
 17. The retractable cover as claimed inclaim 16 wherein each zipper is double sided.
 18. The retractable coveras claimed in claim 14 wherein the affixing means is a hook-and-pilefastener complementarily located on both the cover and the structurewith which the cover is used.
 19. The retractable cover as claimed inclaim 14 wherein the affixing means is magnetic means complementarilylocated on both the cover and the structure with which the cover isused.
 20. A structure incorporating a retractable cover, as claimed inclaim
 1. 21. A method of adapting an existing cover for covering anopening or enclosure, the method comprising the step of: incorporatingthe biasing means to the existing cover.
 22. A method of manufacturing aretractable cover for covering structures, the cover including aflexible material portion, the flexible material portion includingthereon, or adapted to include means for attachment of, at least onebiasing means along the extendable length of the flexible materialportion, the biasing means providing for retraction of the flexibleportion from an extended state to a rolled up state, the methodcomprising the steps of: a) determining the dimensions of the structurewith which the cover is intended to be used and preparing the flexiblematerial portion to the predetermined dimensions, and includingtherewith; and b) biasing means arranged relative to a substantialportion of the extendable length of the flexible portion in a permanentor removable arrangement by use of restraining means, the restrainingmeans being added to or being a portion of the flexible portion.
 23. Amethod of varying retraction of a retractable cover for coveringstructures, the cover including a flexible material portion, theflexible material portion including thereon, or adapted to include meansfor attachment of, at least one biasing means along the extendablelength of the flexible material portion, the biasing means providing forretraction of the flexible portion from an extended state to a rolled upstate, the method comprising the steps of: a) determining one or more ofat least the weight of the flexible material portion, the dimensions ofthe flexible portion, structure to be covered, the retraction force ofthe biasing means; and b) providing additional biasing means.
 24. Themethod of claim 23, wherein the step of providing additional biasingmeans includes the step of: b1) replacing the biasing means with a newbiasing means of greater force.
 25. The method of claim 23, wherein thestep of providing additional biasing means includes the step of: b2)adding additional biasing means to the flexible material portion toeffect a combined retraction force in accordance with predeterminedretraction force requirements.